We show that nutlin-3 (an MDM2 inhibitor that disrupts the MDM2/p53 interaction) and NSC207895 (a small molecule that inhibits the MDMX promoter activity) co-treatment has a profound inhibitory effect on androgen-responsive prostate cancer LNCaP and 22RV1 cells that carry a wild-type copy of the TP53 gene. The gene discussed is MDM2; the disease is prostate cancer.